Usage of passive air samplers in exposure assessment – a look at pesticides

Abstract

The increasing amount of chemicals used around the globe has also increased the risk of disease through exposure to these compounds. A subcategory are pesticides, which are the subject of this study. The focus on monitoring pesticide exposure through food and/or occupational risk leaves exposure through inhalation understudied. Therefore a risk assessment is performed for residents of rural areas in the Netherlands, living near agricultural fields treated with pesticides. To monitor air concentrations of pesticides two main methods are available: Active and Passive air samplers (AAS & PAS). AAS allow for precise measurements but have disadvantages in cost, ease of deployment and noise. PAS do not suffer from these disadvantages however the measurements are still imprecise. The cause is that the precise sampling rate (R) of the PAS has to be estimated. This study utilizes three methods to extrapolate PAS measurements towards ng per cubic meter of air. I) A set value of R = 4, II) windspeed-derived individual sampling rate per PAS, and III) a linear model using environmental conditions. The results of predicted concentrations of each method were compared and varied in precision. For pendimethalin the methods resulted in a r-squared of; I) 0.18, II) 0.18, III) 0.40. The chlorpropham results were; I) 0.31, II) 0.31, III) 0.71. Taking environmental conditions like temperature and humidity into account does show promise. This can enable future research to build further on these kind of models and allow for more accurate estimations using PAS.